Stable Interface Chemistry and Multiple Ion Transport of Composite Electrolyte Contribute to Ultra‐long Cycling Solid‐State LiNi0.8Co0.1Mn0.1O2/Lithium Metal Batteries

• Published in: Angewandte Chemie International Edition 2021-11, Vol.60 (46), p.24668-24675
• Main Authors: Yang, Ke, Chen, Likun, Ma, Jiabin, Lai, Chen, Huang, Yanfei, Mi, Jinshuo, Biao, Jie, Zhang, Danfeng, Shi, Peiran, Xia, Heyi, Zhong, Guiming, Kang, Feiyu, He, Yan‐Bing
• Format: Article
• Language: English
• Subjects: Chemical reactions; composite electrolytes; Composite materials; Dimethylformamide; Electrochemistry; Electrolytes; Fluorides; interface chemistry; Ion currents; Ion transport; Ions; Lithium; Lithium isotopes; multiple ion transport; Nanotechnology; Nanowires; NMR; Nuclear magnetic resonance; Polymers; Polyvinylidene fluorides; Side reactions; solid-state lithium metal batteries; Vinylidene fluoride
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202110917

Severe interfacial side reactions of polymer electrolyte with LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode and Li metal anode restrict the cycling performance of solid‐state NCM811/Li batteries. Herein, we propose a chemically stable ceramic‐polymer‐anchored solvent composite electrolyte with high ionic conductivity of 6.0×10−4 S cm−1, which enables the solid‐state NCM811/Li batteries to cycle 1500 times. The Li1.4Al0.4Ti1.6(PO4)3 nanowires (LNs) can tightly anchor the essential N, N‐dimethylformamide (DMF) in poly(vinylidene fluoride) (PVDF), greatly enhancing its electrochemical stability and suppressing the side reactions. We identify the ceramic‐polymer‐liquid multiple ion transport mechanism of the LNs‐PVDF‐DMF composite electrolyte by tracking the 6Li and 7Li substitution behavior via solid‐state NMR. The stable interface chemistry and efficient ion transport of LNs‐PVDF‐DMF contribute to superior performances of the solid‐state batteries at wide temperature range of −20–60 °C. A ceramic‐polymer‐anchored solvent composite electrolyte with excellent ion transport capability and stable interface chemistry is developed to achieve ultra‐stable cycling stability and superior performances of solid‐state LiNi0.8Co0.1Mn0.1O2/lithium metal batteries at wide temperature range of −20–60 °C. The ceramic‐polymer‐liquid multiple ion transport mechanism is identified by solid‐state NMR.